title: [Gestational age of delivery in multiple gestation].
abstract: OBJECTIVE
  The aim of this research was to find out the average gestational age of delivery in multiple pregnancy and to compare the results with world trend.
  
  
  METHODS
  Retrospective and prospective comparative analysis was used. The study covered 20 years from 1991 to 2011, included 71114 births, 1436 twins, 67 triplets and I quadruplets.
  
  
  RESULTS
  The number of multiple pregnancies in 1991 was 64 and in 2011 was 118. The frequency of twins increased from 1.56% at the beginning of the observed period to 3.44% at the end of the period. The frequency of triplets went from 0.02% to 0.26%. We discovered that the number of twins increased more than twice and the number of triplets - 13 times. Average gestational age of delivery in twins was 35+5 w.g. and in triplets - 31 w.g. 1-min Apgar score in twins was 6.1 and 5-min Apgar score was 7.5. In triplets the results showed that 1-min Apgar score was 5.6 and the 5-min Apgar score was 7.0. At the beginning of the researched period in 1991, 62% of women had vaginal delivery and only 38% Ceasarean section. In 2011 the Ceasarean section was 84% and vaginal delivery only 16%.
  
  
  CONCLUSIONS
  There is a significant increase in the frequency of multiple gestation, observed in twins as well as in triplets. The average gestational age of delivery is earlier compared to world tendencies. The received results of the newborns' health status in the early neonatal period are good. The predominance of Ceasarean section as a mode of delivery is similar to world trend.
authors.forename: I
authors.initials: I
authors.lastname: Petrova
authors.forename: A
authors.initials: A
authors.lastname: Nikolov
authors.forename: P
authors.initials: P
authors.lastname: Markov
authors.forename: B
authors.initials: B
authors.lastname: Slancheva
authors.forename: N
authors.initials: N
authors.lastname: Yarakova
mesh_terms: D001034:Apgar Score; D002031:Bulgaria; D002585:Cesarean Section; D036861:Delivery, Obstetric; D005260:Female; D005865:Gestational Age; D006801:Humans; D007231:Infant, Newborn; D011247:Pregnancy; D011272:Pregnancy, Multiple / Q000706:statistics & numerical data; D011446:Prospective Studies; D012189:Retrospective Studies; D014310:Triplets / Q000706:statistics & numerical data; D014427:Twins / Q000706:statistics & numerical data